videos in AudioSet
A list of about a million ten-second YouTube clips, each labelled with the sounds in it, that Google published in 2017. Labs use it to train and test general audio and music models.
Including Still Alive Instrumental for Classical Guitar (Theme from Mirror's Edge), Donkey Kong Country: Aquatic Ambience for Classical Guitar, Sonic the Hedgehog 2: Aquatic Ruin for Flamenco Guitar :)